Fires in even the most modern multi-story buildings continue to pose an extreme hazard to life. High-rise buildings are particularly susceptible to the risk of fire because existing fire-fighting equipment and ladders will not reach more than the lower floors of such buildings, and access to the upper floors otherwise is only by interior stairs and elevator shafts. This presents a heretofore unsolved problem, because fire fighters find it difficult to get to the location of fire in high-rise buildings safely and quickly either by elevator or by stairway. Moreover, elevators inside a multi-story building often are found to be inadequate or dangerous during a fire because building power and central air conditioning systems are vulnerable to fire and smoke. So, too, many elevators are operated by the temperature of physical contact, which can be disastrous in the event of a fire. Such elevators may ascend or rise to the floor where the fire is burning and stop at that point with their doors open and with the occupants unable to move it in either direction. Lastly, stairways and elevator shafts often become air ducts for ascending smoke and heat and thus are not dependable as a means for building occupants or fire fighters to ascend or descend the building. A variety of publications have documented the aforesaid hazard to life, as evidenced in U.S. Pat. No. 4,018,306.
A number of rescue mechanisms for evacuating the occupants of a multi-story building in the event of fire have heretofore been described. These prior art systems generally are set forth in U.S. Pat. No. 4,018,306. Prior art devices also are typified by U.S. Pat. Nos. 284,180; 836,008; 3,860,092; 3,931,868; 4,018,306; 4,111,281; 4,121,693; and 4,122,917. Each of these prior art references shows efforts to devise external rescue devices which are dependable. None of the prior art devices, however, have met this need. For example, U.S. Pat. Nos. 284,180 and 836,008 show baskets which are raised and lowered by a fixedly positioned pulley. U.S. Pat. Nos. 3,860,092 discloses a complicated system involving at least five persons and using a succession of increasingly heavier cables. U.S. Pat. No. 4,018,306 discloses a system which is primarily designed for use along fixed vertical rails on the side of a building. It teaches that rescue be made only at emergency access openings provided in the building at locations adjacent the vertical railroad tracks. It further discloses the use of a complicated system of pulleys purportedly to maintain stability of a rescue vehicle. U.S. Pat. Nos. 4,111,281 and 4,121,693 and 4,122,197 each disclose various arrangements for rescue systems which present problems of system stability. None of these prior art systems have found public acceptance.
Thus, while the need for a dependable and expeditious yet reasonably economical apparatus to evacuate the occupants of a multi-story building has long been apparent, this need has not been met in the prior art. This is especially true for high-rise buildings. It is an object of this invention to overcome the prior art deficiencies and provide a rescue system which can be placed into operation within minutes, is inexpensive for the municipality or city to operate, and is inexpensive for building owners.